Cardiovascular System Flashcards
What are the functions of the cardiovascular system?
To transport oxygen, nutrients and hormones TO cells and waste products AWAY from cells. Distributes heat around the body.
What are the average blood volumes?
Adult female - 5 Litres
Average Full Term Baby - 300mls
Average 30 week pre term baby - 100mls
What are the 3 layers of the heart wall?
Endocardium. Myocardium. Pericardium.
What is plasma?
The substance which red and white blood cells are suspended in. It is 92% water.
What are erythrocytes?
Red blood cells. Most abundant cells in the body. Their cytoplasm is rich in haemoglobin which transports oxygen around the body.
What ate Leucocytes?
White blood cells. Involved in protecting the body against both infectious disease and foreign invaders.
Name 4 different types of Leucocytes.
Lymphocytes. Neutrophils. Monocytes. Macrophages.
What are platelets?
Tiny pieces of cells that begin the clotting process and plug up injured blood vessels. Also known as thrombocytes.
What does the aortic arch immediately branch off into as it leaves the left ventricle?
Brachiocephalic trunk. Left common carotid artery. Left subclavian artery.
How many layers of tissue make up arteries?
3 - Tunica Externa, Tunica Media and Tunica Intima. Blood flows through the internal space known as the lumen.
What does the Inferior Vena Cava do?
Returns blood from below the heart.
What does the Superior Vena Cava do?
Returns blood from above the heart.
Describe the flow of blood in one heartbeat.
Deoxygenated blood enters right atrium from vena cava.
It passes through the tricuspid valve to the right ventricle.
It passes through the pulmonary semilunar valve to the pulmonary artery.
Travels through pulmonary artery to lungs for oxygenation.
Blood returned from lungs in pulmonary veins into left atrium.
It passes through the mitral valve to left ventricle.
It passes through the aortic semilunar valve into the aorta to be pumped to rest of body.
What is the sinoatrial (SA) node?
Considered to be the heart’s pacemaker. Becomes self stimulating once nervous input establishes rhythm. Located on back wall of right atrium.
What is atrioventricular (AV) node?
A small mass of tissue located in right atrium, near septum. Relays impulses from SA node to next part of conduction system.
